Process of producing wool fabrics exhibiting unidirectional stretch



Oct. 25, 1966 L. A. RUNTON PROCESS OF PRODUCING WOOL FABRICS EXHIBITING UNDIRECTIONAL STRETCH Filed March 13, 1965 SOLUTION CONTROL BOX 35 AUTOCLAVE SCOURING UNlT FIG. I

4 Sheets-Sheet 1 INVENTOR LESLIE A. RUNTON ATTORNEY- 4 Sheets-Sheet 2 INVENTOR LESLIE A RUNTON O O O O ATTORNEYS Oct. 25, 1966 A. RUNTON PROCESS OF PRODUCING WOOL FABRICS EXHIBITING UNDIRECTIONAL STRETCH Filed March 13, 1963 xom 405200 xom 405.200

xom 40528 PERCENT EXTENSION AT A LOAD 0F O.lg /DENIER PERCENT CHANGE lN EXTENSION,

Oct. 25, 1966 Filed March 13, 1963 L- A. RUNTON I PROCESS OF PRODUCING WOOL FABRICS EXHIBITING UNDIREGTIONAL STRETCH 4 Sheets-Sheet 5 FILL FABRIC A FABR C B FABR C C W 413M L o o FILL 0 I \O\O\ WARP O O\ T WARP WARP 0 IO 20 0 I0 20 0 I0 20 TENSION, LBS CONTINUOUS TREATMENT BATCH TREATMENT (6 LBS TENSON) FABRIC A w L WARP FILL wARP FILL FABRIC B FABRIC C INVENTOR.

LEsLIE A RUNTON BY MOI/d A TTOR NE Y5 593 3122i 55 ow 4 Sheets-Sheet 4- L. A. RUNTON UNDIRECTIONAL STRETCH INVENTOR LESLIE A. RUNTON wmm, SM

J74 ATTORNEYJ' PROCESS OF PRODUCING WOOL FABRICS EXHIBITING Oct. 25, 1966 Filed March 13, 1965 'OHVA HVHNI'I 83d SHONHO NI lHSIEIM SIHBVJ GEIHSINH United States Patent 3,281,205 PROCESS OF PRODUCING WOOL FABRICS EX- HIBITING UNIDIRECTIONAL STRETCH Leslie A. Runton, Middle Haddam, Coun., assignor to J P.

Stevens & Co., Inc., New York, N.Y., a corporation of Delaware Filed Mar. 13, 1963, Ser. No. 264,908

The portion of the term of the patent subsequent to Feb. 19, 1980, has been disclaimed 16 Claims. (Cl. 8-128) This application is a continuation-in-part of copending applications Serial No. 75,394 filed December 12, 1960; Serial No. 118,217 filed May 9, 1961 now US. Patent 3,077,655; Serial No. 151,827 filed Nov. 13, 1961 now abandoned; and Serial No. 182,535 filed March 26, 1962.

This invention rel-ates to woven wool fabrics composed entirely or in part of wool, which fabrics have characteristics hitherto unattainable, and to methods of preparing the same.

An object of this invention is to provide fabrics composed wholly or partly of wool which possess recoverable stretch in at least one direction.

A further object of this invention is to provide fabrics composed wholly or partly of wool characterized by tailorability, excellent wrinkle recovery, good drape, shape retentivity, crease retention, and excellent hand.

A further object is to provide faJbrics wherein fiber migration and fuzzin-g in the conventional wool finishing operation and in the laundering and dry cleaning of the garments made from these fabrics is minimized whereby a clear definition of the individual yarns constituting the fabrics is retained in superior measure.

A further object of this invention is to provide a method of making wool and wool-containing fabrics characterized by recoverable stretch in at least one direction, by superior tailorability, excellent wrinkle recovery, good drape, crease retention, and shape retentivity.

Other objects of this invention will be apparent from the following description, examples and claims.

In accordance with this invention, the fabric which can consist entirely or partly of all-wool yarns or of yarn composed of a blend of at least 30% wool with other staple fibers as received from the weaving stage, and with or without size and in dyed or undyed state, is impregnated with a solution of a chemical stabilizing or relaxing agent, for example, by being passed through such a solution and thereafter squeezed to remove excess liquid. It is then heated, for example, by exposure to steam while free from constraint in at least one direction.

More specifically, the fabric is impregnated with a solution of the relaxing agent, and when the excess solution is removed by squeezing, it contains from about 50 to 130% of liquid based on the dry weight of the fabric. The concentration of the relaxing agent will be chosen so that at the pick-up employed the desired amount of reagent is on the fabric. In order to permit full relaxation of the impregnated fabric, it is heated, for example, by steaming at a temperature between about 210 F. and 225 F. for a time ranging from /2 to 4 minutes. -If a lower steam temperature is employed, the time needs to be prolonged to effect full relaxation; and conversely, if a higher steam temperature is utilized, a shorter time is required. While steam is preferred, the fabric may be heated by other means. The temperature to "ice which the fabric may be subjected is preferably at about i the boiling point of the relaxing agent, although it is apparent that the temperature need only be that which is sufficient to impart a permanent set to the crimped yarns.

When a fabric containing wool fibers is impregnated with a relaxing agent and is heated in the presence of moisture, the wool fibers relax and develop a high degree of crimp, whereby the yarns and consequently the fabric shrinks in the direction which is free from constraint. For example, if the fabric is free from tension or constraint in the filling direction, it can be shrunk weftwise in the heating step zone as much as 6 to 25% or greater without appreciable shrinkage in the Warpwise direction. The amount of shrinkage in the weftwise direction, and consequently the amount of recoverable stretch, can be regulated by controlling the amount of tension applied to the fabric in the warp direction while it is in the heating zone; for example, by increasing the amount of tension in the warp direction, the amount of shrinkage in the weft direction is increased. While a tension of from 5 to 200 lbs. applied to a fabric having about a 60 inch width gives the desired results, the amount of tension will vary depending upon the particular fabric being treated and the weight thereof. Preferred values for various types of fabrics with various warp yarn structures are illustrated in the chart of FIG. 4.

On the other hand, if the fabric is free from constraint in both weft and warp directions, it can be shrunk as much as 20% in each of the two directions.

After the heating or relaxing step, it is desirable to cool the fabric immediately, such as by immersing it in cold water, by spraying with cold water, or by aspirating cool air through the fabric.' The impact of this cooling action serves to further set the wool fibers in their rel-axed or crimped state. Further fixation of the fabric can be accomplished by a subsequent treatment with any of the reagents known in the art for fixing relaxed keratin fibers. The stabilization resulting from the treatment of this invention imparts a. permanent set to the fabric and its component yarns. Consequently, when a thread is withdrawn from the fabric and immersed in hot Water, it retains its crimp, whereas a thread withdrawn from a conventionally finished fabric tends to straighten.

Representative of the relaxing or stabilizing agents usable in the present invention are such well known reducing agents for W001 as the sulfites, bisulfites, sulf-oxyl'ates, and hydrosulfites. These can be used as the alkali metal, ammonium, or organic amine salts. Other such reducing agents are substituted mercaptans, for example, mercaptoacids or mercapto-alcohols, the alkali metal boro-hydrides, and the alkali metal stannites. However, the preferred relaxing agents are the aqueous solutions of organic amine sulfites (or bisulfites), such as those disclosed in US. Patent No. 2,437,965, including a solution of monoeth-anolamine sulfite in about 110% concentration, although .a greater concentration may be used. The other agents may be used in concentrations which would give the equivalent effect.

Representative of the fixing agents which can be employed "following the relaxing and cooling steps in the present invention are dilute solutions of aliphatic carboxylic acid-s such as formic or acetic acid; mild alkalis such as dilute solutions of alkali metal carbonates; solutions of oxidants such as hydrogen peroxide or sodium carbonate will be the preferred fixing agent.

The relaxing reagents employed in the present process are well known in the art of imparting permanent set to all-wool fabrics in the fiat, pleated and creased-form. These reagents have also been employed to relax specially constructed wool fabrics composed of high-twist yarns so as to develop crepe effects. The high-twist worsted yarns which are necessary for making wool crepes have a singles twist factor (turns per inch per square root of ,of the worsted count) greater than 4.5 and usually about 5.0. However, I have made the surprising discovery that when wool and wool-containing fabrics constructed of conventional twist yarns, that is, with a twist factor ranging from 1.5 to 4.0 are treated by the process of this invention, fabrics are obtained which are characterized (a) by possessing recoverable stretch in at least one direction; (b) by having a clear smooth surface rather than either a creped or fuzzy surface, and (c) by exhibit- .ing highly desirable characteristics with respect to tailorability, hand, crease resistance, wrinkle recovery, and

.shape retention.

It is to be appreciated that all fabrics, including wool fabrics, have the ability to be stretched a limited amount in any direction by the application of a stretching force thereto. However, it is to be understood, for purposes of this invention, that when I speak of imparting a stretch property or characteristic to the wool or wool-containing fabrics, I mean that this amount of stretch is in addition to the amount of stretch properties of the fabric. Thus, if a wool fabric has an inherent stretchability of 4% of its width, I can impart an additional 6% stretch property thereto so that the fabric can be stretched to 10% of its width.

While the process of the invention can be carried out as a batch process whereby uncontrolled shrinkage of the fabric will occur in both yarn directions, it is a further feature of my invention to carry out the process as a continuous process whereby the amount of stretch imparted to the fabric in any direction can be unexpectedly controlled.

Fabrics which may be treated in accordance with this invention must be woven so as to have sufiicient space between adjacent yarns to accommodate the desired yarn crimping and the resulting fabric shrinkage.

An apparatus suitable for carrying out the present invention by a continuous process is illustrated in the accompanying drawings, wherein:

FIGS. 1 and 1a, when joined at the vertical lines 22, together constitute a schematic sectional view of such apparatus.

With reference to FIGS. 1 and la of the drawings, there is shown an apparatus for carrying out the present invention by a continuous process. A strip of fabric 10 of the type above described is fed from a supply roll 9 by feed rolls 11 into a J-box 12 where it forms a series of loose folds. It is withdrawn from the J-box 12 over a roll 13 and is introduced between guide rolls 14 into a tank 15 containing a relaxing solution of the type referred to above. The fabric strip 10 passes in a succession of fold-s under a set of lower rolls 16 and over a roll 17, :he former being immersed in the solution of tank 15.

From the tank 15 the fabric 10 passes over a roll 18 nto a tank 19 under a roll 20 which is submerged in the relaxing solution in the tank, thence over a roll 21 to the 4 bite of a pair of squeeze rolls 22 and 23. A drain 19' returns the solution from the tank 19 to the tank 15.

The upper roll 22 is loaded so as to leave a pick-up of about 50 to percent of the fabric weight. The lower roll 23 dips into the solution in tank 19.

From the squeeze rolls 22 and 23 the fabric passes over a guide roll 24, under a control roll 25, over a guide roll 26 and under a guide roll 27 into an autoclave 31 through a vestibule 33 having a seal 34 to minimize the escape of steam. The control roll 25 actuates a control box 28 which is connected to control the drive of the rolls 22 and 23 in sequence to maintain the fabric strip entering the autoclave under a constant tension in the warp direction. In the autoclave 31 the fabric passes around a series of upper rolls 35 and a series of lower r-olls 36 in the form of a series of vertical loops. Steam is supplied to the space below the lower rolls 36 from a supply pipe 37 through a series of headers 38.

In the autoclave the steam, which is at a temperature of about 210 to 225 F., is maintained at a slight pressure above atmospheric which in conjunction with seal 34 prevents the entrance of any air. The fabric is unconfined laterally so that it is free to shrink in width during this treatment While the rolls 35 and 36 hold the fabric flat and in unwrinkled condition.

The rolls 35 and 36 in the autoclave are driven at a predetermined rate by a suitable adjustable variable-speed drive mechanism not shown. The rate may be adjusted in accordance with the time which the fabric is to remain in the autoclave, which time is preferably in the range of /2 to 4minutes.

The fabric passes from the autoclave through an exit vestibule 39 having a seal 40 around guide rolls 41, under a control roll 42 and over a guide roll 43 into a full-width cloth-scouring unit 60, known as a Williams unit, of standard construction having a series of upper rolls 46 and a series of lower rolls 47 around which the fabric passes in a series of loops between fixed plates 48 which lie closely adjacent the loops. A spray of cold water is applied to the fabric in this scouring unit from a spray header 49. This spray immediately cools the fabric to a temperature to stop the chemical action, and also removes a large portion of the treating agent.

The scouring liquid is maintained in the scouring unit at a level slightly below the rolls 46 so that the fabric advances through this liquid as it feeds through the unit. From the scouring unit 60 the fabric passes over a guide roll 50 into the bite of a pair of feed rolls 51 and 52, the latter of which dips into the liquid in a tank 53 which drains into the scouring unit through an overflow 54. The control roll 42 is adapted to control the rate of the feed rolls 51 and 52 so as to maintain the fabric under a constant tension in its passage through the apparatus.

From the feed rolls 51 and 52 the fabric passes through a series of units 60A, 60B and 60C which are substantially identical with the unit 60 and the corresponding parts of which have been given similar reference numbers with the suflixes added. Each unit is followed by a pair of feed rolls 51a, 52a, 51b, 52b, 51c and 52c respectively. Each pair of feed rolls is followed by a control unit composed of fixed rolls 41a, 41b and 41a, 43a, 43b and 43a and a movable control roll 42a, 42b and 420 respectively. Each control roll is connected to control the rate of the preceding pair of feed rolls so as to maintain the fabric under a constant tension in the corresponding unit.

The unit 60A can contain a fixing agent of the type described above. The unit 60B'can contain a desizing solution for removing any size remaining on the fabric. If the fabric is unsized or if it is not desired to remove the size, this unit may be omitted. The unit 60C can contain wash water to remove the fixingand desizing solutions.

From the unit 60C the fabric passes under a roll 65 in a tank 66 containing rinse water for a final'rinse. Rinse water is supplied from a spray header 67 onto the fabric as it enters and leaves the tank 66. From the tank 66 the fabric passes between a pair of squeeze rolls 68, thence to a folder 70 which may be of standard construction and is adapted to lay the fabric in a series of folds 71. The fabric is then taken to a drying stage such as a slack loop dryer, not shown, or a slack tray dryer or a hot air dryer of any standard type, wherein the cloth is dried in a relaxed state.

As already noted, the uncontrolled imparting of stretch properties to wool or wool-containing fabrics can be carried out by -a batch process. For this purpose, several of the conventional wool-finishing machines can be used. For example, the fabric can be impregnated with the stabilizing or relaxing solution and wound on the perforated drum of a decating machine together with a cotton leader cloth, care being taken to wind with a minimum of ten sion so that the fabric is free to shrink. Steam is then blown through the perforations in the drum for about 2-4 minutes, and the fabric is then cooled by aspirating air through it by means of a vacuum pump for several minutes. The fabric is then unwound, excess water is removed by hydroext-raction, and the fabric is dried in a tension-free state in a slack loop drier or slack tnay drier of the conventional design.

Another conventional wool-finishing machine which can be eifectively employed for carrying out this invention by a batch process is a pressure piece-dyeing machine wherein the fabric is wound on a perforated roll with minimal tension without a leader cloth. The process can then be carried out in the same manner as described above for a decating machine. Alternatively, the fabric can be wound on the roll without being previously impregnated with the relaxing solution. In this instance, the Wound roll of fabric in the machine is immersed in the relaxing solution which is then heated and circulated through the fabric to effect the desired relaxation. The fabric can then be cooled by replacing the relaxing solution with cold water, and thereafter a fixing solution can be circulated therethrough. The fabric can then be subjected to the further steps of extraction and drying as mentioned above in connection with the decating machine.

It is to be understood that whether a batch or continuous process is employed with the present invention, the fabric either before or after drying may be subjected to other standard finishing steps, such as dyeing or the like.

It is to be further understood that the present invention is applicable to all types of woven wool and part-wool fabrics, consisting of two. sets of yarns, namely, weft and warp yarns, except creped fabrics, containing at least 30% wool in one set of yarns, the remainder being synthetic or 7 natural staple fibers such as polyester, polyamide, acrylic, rayon, or cotton fibers. stretch in only one set of yarns or in one direction is desired, the yarns in the other set can be composed entirely of the aforementioned synthetic or natural (non-wool) staple fibers.

The amount of stretch in either direction will depend on the amount of tension applied duringthe weaving as Well as on yarn size and number of yarns per inch.

By the disclosed processes of the present invention, one may contract a wool or wool-containing fabric by crimp ing either the warp yarn or the filling yarns,'or both, so

It will be evident that when.

that the effective length or width, or both, of the fabric is reduced by at least 6% in the particular direction or directions. This means that while the fabric is chemically set at this reduced size, it can be effectively stretched by the same amount, with the fabric returning to its chemically set and reduced size after the stretching force has been removed. The amount of crimping of the yarns and therefore the amount of stretch imparted to the fabric is preferably from 6% to about 25 although a stretch characteristic up to 40% and even 50% can be imparted to the fabric.

The following examples will further illustrate my inunderstood that my invention is not limited to the particular conditions and materials recited in these examples.

EXAMPLE I Three fabrics were treated by the process of this invention using the continuous method described above. The composition and construction of these fabrics is given Table 1 Fabric A Fabric B Fabric 0 Type All-wool wor- Woolen, Warp, 50:50 Woolsted suiting. worsted fill Dacron wordress fabric. sted suiting. Dyein Ton Piece Piece. Weave Plain Plain Plain. Yarn Counts:

Warp 2/50 W 5% run 1/32 Wst. Filling 2/50 Wst 1/19% W512-.. 1/32 WSt. Singles Yarn Twist:

'I.p.i. warp 16% 12 18. T.p.i. filling 16% 13 l8. Worsted Twist Factor:

Warp 2.3-.- 3.0.-.. 3.2. Fillin 2.3.-- 2 9 3.2. Fabric Counts 59 x 39 X41 68 x 54. Weight, ozs/sq. yd. 5.0 4.8 4.2.

Fabric A was used in the greige state; fabrics B and C were prepared by crabbing, scouring and drying.

In the treatment, 18-inch wide strips of fabric were employed; the relaxing agent was 3% aqueous solution of monoethanolamine sulfite, pH 7.25, containing 0.3% of a non-ionic wetting agent. The impregnated fabric, after passing between a pair of squeeze rolls, loaded 'with a pressure'of 50 lbs. per square inch, had a 60-70% pickup of reagent solution. It then passed through the tensioning device, into the steam chamber which was at a temperature of about 218 F. and in which the fabric resided for about 66 seconds. The warpwise tension applied to the fabric during these treatments was varied over the range 'of 3-18 lbs., which corresponds to a range of 10-60 lbs. for a full width of 60 inches.

On leaving the steam chamber, the fabrics were plunged into cold water, squeezed, and then immersed in a fixing solution of 0.25% formic acid. After removal of excess liquid, they were dried without tension.

EXAMPLE II The three fabrics described in Example I were treated by the process of this invention using the batch method. Strips of fabric 5 feet long and 6 inches wide were employed in this treatment, which was performed in a laboratory pressure dyeing machine made by'the Gaston County Machine Company. The strips wereimpregnated with 3% solution of -rnonoethanolamine sulfite by padding and squeezingto a 60-70% pick-up. 'A 1% inch diameter stainless steel dye-tube was covered with three layers 215 F. After 2 minutes of steaming, the machine was filled with cold water, and formic acid was added in suflicient quantity to make a 0.25% solution. After 5 minutes of circulation, the machine was emptied, and the tube removed and unwound. The fabric samples were hydroextracted and dried at 21'2-220" F. while spread out fiat without tension.

The extensibility of the fabrics of Examples I and II was tested at 65% relative humidity, 70 F., on the Instron Tensile Tester, using the procedure described on pp. 117-118 of Technical Bulletin N1, Stretch Woven Fabrics, Chemstrand Corporation, 'March 1962. The testsconsist in determining the behavior of the fabric 1n repeated deformation up to a stress of 0.1 g./denier.

(The procedure as given was departed from in one detail: the test length employed was 4 in. instead of 10 in.) In the table below, one of the characteristics measured in this test, the percent extension at a load of 0.1 g./denier, is given for the fabrics subjected to the various treatments described in Examples I and '11. Each value represents the mean of three or more tests.

The effect of the warpwise tension applied during the The relaxing agent was a 3 aqueous solution of monoethanolamine sulfite at pH 7.1 containing a small amount of wetting agent. The steaming time was 23/: minutes, the temperature in the autoclave being 212-21 8 F. In the fixing step, a 0.2% solution of formic acid was employed. The finishing was completed by beck dyeing (in the case of fabrics D, *E, and G), drying in a slack tray drier, and semidecating.

The width of the fabrics was then measured, and their stretchability in both yarn directions was determined in the following manner: swatches of fabric were cut 24 inches long in the test direction and 8 inches wide in the other direction and were exposed to standard atmosphere of 65% relative humidity, 70 F., for a minimum of 4 hours. Two marks, parallel to the short sides of each swatch, were made 1 8 inches apart. One short edge of the swatch was then attached to a 6-inch-wide hanging clamp, and another clamp of the same width was attached to the lower, free-hanging, end of the swatch. A weight was then added to the lower clamp which, added to the weight of the clamp itself, created a total load of 5 lbs. The distance between the two marks in the fabric was then measured, and the percentage stretch of the fabric calculated. The results obtained with the four fabrics continuous process on the extensibility of the fabric in 25 are fi ded in the table below: both directions is clearly illustrated 'by the graphs of T bl 4 FIG. 2; it is evident that, as the tension is increased, the filling extensibility tends to increase, and the warpwise Stretch ercent extensibility to decrease. In contrast, the batch treat- Fabric 'ment increases the extensibility in both directions to Warp Fm approximately the same extent;'the relative proportions of warp-wise and fillingwise extensibility imparted vary 4 0 15 5 somewhat with the fabric construction and treatment 510 19:0 conditions. g g The difference in result given by the two forms of treatment is illustrated in FIG. 3, the bar graphs of which represent the change in extensibility from the untreated j fabrics. m 'q to .thelr stretchablhty hibited a superior clarity of finish, a soft hand, good to the treated state.

drape, resistance to wrinkling at high 'huirnidity, and a EXAMPLE H1 40 high degree of tailorability. The data of this example demonstrate that the benefits derived from this invention Four pieces of all-wool fabric were treated by the are applicable to a wide variety of wool-containing fabrics process of hi i ti using h continuous h d, of conventional construction, made from either worstedin the device shown in FIGS. 1 and 1a. The composition ype yarns or from Woolen-Spun yarns, or from a combiand construction details of the fabrics are given below: natlon f bot The following table gives further illustrative examples Table 3 of fabric constructions obtained by the batch process:

Fabric D Fabric E Fabric F Fabric G Mens suiting--- Dress Mens suitingm. Women's flannel. Piece- Piece. Top Piece. Plain Plain Plain 2/1 Twill. Yarn Counts:

Warp- 1/24 Wst 5% run 2/50 Wet 4.4 run. F1llirig 2150 we 1/20 Wst 2/50 Wst 4.4. run. Singles Yarn Twist:

T. .i. Warp 1s 15 17 12%. 'I.p.i. Fillin 17 is 11 12%. Worsted Twist Factor:

Warp s i 3.8- 2.4- 3.5. Filling" 2.4- 2.9- 2.4- 3.5. Tension (lbs. per inch finished 100 22 100 33.

width). Fabric Counts, finished x 52 41 x 40 69 x 52 51 x 33. Width, inches, finished 59 58%. 58 54. Weight, oz./yd., finished 9M 9% 9 12.

Table 5 I Turns per Yarn Size Worsted War E (3 er In h i E Fabric Inch of S Z-Ply Worsted Twist p n s p c We t nds pet Inch 'I wist Counts Factor, Singles Singles Before After Before After 22 14 2/60s 2.8 49 60 42 51 18 20 2/60s 2.3 68 74 68 77 17 18 2150s- 2.4 68 72 52 64 16% 17 2/46s 2.6 49 60 42 52 15 17 2/40s- 2.4 53.5 59 4s 59 12 s 2/30s-.- 2.7 as 42 40 44 While the above table indicates two-ply yarns, it will be evident that singles yarns of the equivalent sizes may be used for either warp or weft, or both, in place of the two-ply yarns specified.

While the illustrative embodiments of the invention have been described hereinbefore with particularity, it will be understood that various other modifications will be apparent to and can readily be made by those skilled in the art without departing from the scope and spirit of the invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the examples and description set forth herein but rather that the claims be construed as encompassing all the features of patentable novelty which reside in the present invention including all features which would be treated as patentable equivalents thereof by those skilled in the art to which the invention pertains.

Having fully described the invention, what is claimed 1. A method of making a woven stretch fabric from a woven fabric having a set of weft yarns and a set of Warp yarns at least one set of said yarns containing at least 30% wool, said other set of yarns being spaced to permit shrinkage of the fabric in the direction of said wool-containing yarns, comprising treating the woven fabric with a relaxing agent at an elevated temperature while tension is imparted to said other set of yarns, said temperature being sufiicient to increase the density of said other set of yarns and to increase .the crimp frequency of said wool-containing yarns by at least 6% and to impart a permanent set to said yarns, and drying the fabric in its permanently set state to thereby produce a stabilized fabric which is stretchable in the direction of said woolcontaining yarns by at least 6% and is capable of returning to its stabilized state when the stretching force is released.

2. The method as defined in claim 1 including the step of cooling the treated fabric to arrest the chemical action of the relaxing agent therewith and then drying the treated fabric.

3. The method as defined in claim 1 wherein the crimp frequency of the weft yarns is increased from 6% to about 50%.

4. The method as defined in claim 1 wherein said relaxing agent is a reducing agent for keratin.

5. The method as defined in claim 1 wherein said relaxing agent is a solution of a sulfur-containing reducing agent for W001.

6. The method as defined in claim 1 wherein said relaxing agent is a solution of an organic amine sulfite.

7. The method as define-d in claim 1 wherein said relaxing agent is an aqueous solution of a monoetholamine sulfite.

8. The method as define-d in claim 1 wherein said temperature is within the range of about 210-225 F.

9. The method as defined in claim 1 wherein said woven fabric has its fibers arranged in yarns which have a worsted twist factor of about 1.5 to 4.0.

10. The method as defined in claim 1 wherein said warpwise tension applied to said fabric is within the range of about to 200 lbs.

11. The method as define-d in claim 1 wherein said warpwise tension applied to said fabric is within the range of about 10 to 80 lbs.

12. A method of continuously making a woven stretch fabric having a controlled amount of stretch therein from a woven fabric having a set of weft yarns containing at least 30% wool and a set of warp yarns, said warp yarns being spaced to permit weftwise shrinkage of the fabric, comprising treating the woven fabric with a relaxing agent at an elevated temperature while tension is imparted to said set of warp yarns, said temperature being sufiicient to increase the density of said warp yarns and to increase the crimp frequency of the weft yarns by at least 6% and to impart a permanent set to said yarns, and drying the fabric in its permanently set state while maintaining said tension in the warp yarns to thereby produce a stabilized fabric which is stretchable in the weft direction by at least 6% and is capable of returning to its stabilized state when the stretching force is released.

13. A method ofcontinuously making woven stretch fabric from a woven fabricconsistin-g essentially of wool and having weft yarns and warp yarns with said yarns being spaced to permit shrinkage of the fabric, comprising the steps of passing said woven fabric war-pwise through a first zone and wetting said fabric with a relaxing agent while in said first Zone, further passing said wetted fabric through a second zone and maintaining a warpwise tension of from 5 to 200 pounds on said fabric as it passes through said second zone, subjecting said wetted fabric in said second zone while in a smooth state to a temperature at about the boiling point of said relaxing agent for thereby increasing the crimp frequency of the weft yarn by at least 6% and imparting a permanent set thereto to thereby produce a stabilized fabric which is stretchable by at least 6% in the weftwise direction and is capable of returning to its stabilized state when the stretching force is released.

14. A method of continuously making a woven stretch fabric from a woven fabric consisting essentially of wool and having weft yarns and warp yarns with said yar-ns being spaced to permit shrinkage of the fabric, comprising the steps of passing said woven fabric warpwise through a first zone and wetting said fabric with a relaxing agent while in said first zone, further passing said wetted fabric to steam in said second zone while in a warpwise tension of from 10 to pounds on said fabric as it passes through said second zone, subjecting said wetted fabric to steam in said second zone while in a smooth state so as to increase the crimp frequency of the weft yarns by at least 6% and impart a permanent set thereto to thereby produce a stabilized fabric which is stretchable by at least 6% in the weftwise direction and is capable of returning to its stabilized state when the stretching force is released.

15. A method of continuously making a woven stretch fabric from a Woven fabric having weft yarns and warp yarns and said yarns being spaced to permit desired shrinkage of the fabric, at least one of the sets of yarns containing at least 30% wool fibers, comprising wetting said woven fabric with a relaxing agent, applying from 10 to 80 pounds tension to one set of said yarns to permit said other set of yarns containing said wool fibers to move relative thereto, subjecting the woven fabric while in a smooth state in the presence of said relaxing agent to a temperature sufficient to increase the crimp frequency of said yarns containing wool fibers by at least 6% and impart a permanent set thereto to thereby produce a stabilized fabric, which is stretchable by at least 6% in the direction of said wool containing yarns, and is capable of returning to its stabilized state when the stretching force is released.

16. A method of making a woven stretch fabric having a predetermined amount of recoverable weftwise stretch therein without affecting the warpwise stretch properties thereof, consisting essentially of treating a woven fabric having a set of weft yarns containing at least 30% wool fibers and a set of warp yarns, wherein said warp yarns are spaced to permit weftwise shrinkage of the fabric, with a relaxing agent at an elevated temperature while imparting from 5 to 200 pounds tension on said set of warp yarns, said temperature being sufficient to increase the density of said warp yarns and to increase the crimp frequency of said weft yarns by at least 6% and to impart a permanent set to the yarns, and drying the fabric in its permanently set state while maintaining said tension on the warp yarns to thereby produce a stabilized fabric which is stretchable in the Weft direction by at least 6% and is 1 1 capable of returning to its stabilized state when the stretching force is released, the stretch properties of said treated fabric in the Warp direction being substantially those of the untreated fabric.

References Cited by the Examiner UNITED STATES PATENTS Foster 28-76 Sherman 2876 Stuewer et a1. 28--76 Seltzer 139--383 Runton 8128 NORMAN G. TORCHIN, Primary Examiner. RUSS-ELL C. MADER, L. K. RIMRODT, I. CANNON,

Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,281,205 October 25, 1966 Leslie A. Runton It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the heading to the drawings, Sheets 1 to 4, line 3 thereof, for "UNDIRECTIONAL", each occurrence, read UNIDIRECTIONAL Signed and sealed this 5th day of September 1967.

( AL) Attest:

ERNEST W. SWmER Attesting Officer EDWARD J. BRENNER Commissioner of Patents 

1. A METHOD OF MAKING A WOVEN STRETCH FABRIC FROM A WOVEN FABRIC HAVING A SET OF WEFT YARNS AND A SET OF WARP YARNS AT LEAST ONE SET OF SAID YARNS BEING SPACED TO LEAST 30% WOOL, SAID OTHER SET OF YARNS BENG SPACED TO PERMIT SHRINKAGE OF THE FABRIC IN THE DIRECTION OF SAID WOOL-CONTAINING YARNS, COMPRISING TREATING THE WOVEN FABRIC WITH A RELAXING AGENT AT AN ELEVATED TEMPERATURE WHILE TENSION IS IMPARTED TO SAID OTHER SET OF YARNS, SAID TEMPERATURE BEING SUFFICIENT TO INCREASE THE DENSITY OF SAID OTHER SET OF YARNS AND TO INCREASE THE CRIMP FREQUENCY OF SAID WOOL-CONTAINING YARNS BY AT LEAST 6% AND TO IMPART A PERMANENT SET TO SAID YARNS, AND DRYING THE FABRIC IN ITS PERMANENT SET STATE TO THEREBY PRODUCE A STABILIZED FABRIC WHICH IS STRETCHABLE IN THE DIRECTION OF SAID WOOLCONTAINING YARNS BY AT LEAST 6% AND IS CAPABLE OF RETURNING TO ITS STABILIZED STATE WHEN THE STRETCHING FORCE IS RELEASED. 